1. Field of the Invention
The invention is directed to a shiftable disk clutch or disk brake. The shiftable disk clutch is preferably used in the drivetrain of a ship between a prime mover and a ship's propeller shaft.
2. Discussion of the Prior Art
Known ship drive systems, especially for shuttle tankers, include a diesel engine, especially a two-cycle diesel engine, which is in driving connection with a ship's propeller shaft by means of a flexible, non-shiftable clutch and a tooth clutch. The ship's propeller shaft is provided with an axial pressure bearing for receiving axial thrust or shear forces. The shaft connection arranged between the flexible clutch and the tooth clutch can be provided with a power take-off gear unit (PTO or power take-off drive) for driving an electric generator and/or other units in the ship. During driving operation of the ship, the ship's engine drives the propeller shaft and, by way of the power take-off, also the onboard generator. The ship's propeller shaft must be disconnected from the ship's drivetrain so that the onboard generator can also be driven when the ship is stopped, for example, when the ship is docked. This disconnection is carried out by opening the tooth clutch. However, the tooth clutch can only be opened or closed when both the engine shaft and ship's propeller shaft are at a complete stop.
In the prior art, this opening and closing of the tooth clutch is carried out manually, wherein it is very time-consuming and difficult when closing the tooth coupling to align the teeth of one clutch part with the tooth spaces of the other clutch part and bring them into engagement. For this purpose, the ship's propeller shaft must often be blocked so that it will not be turned by the movement of the water. The ship's driving engine must be driven at a slow rate of rotation and switched off in an exact manner while taking into account the slow-down or run-out path such that the engine shaft aligns the teeth of one clutch part with the tooth spaces of the other clutch part. A further disadvantage of the tooth clutch is that it cannot be remotely operated, but must be actuated manually in situ. The engagement and disengagement of the tooth clutch must be carried out a number of times in a day, for example, if the ship in question is a shuttle tanker.
Another disadvantage of the tooth clutch is that the teeth of one clutch part must have some clearance or play in the tooth spaces of the other clutch part so that they can engage. However, this results in vibration problems and the teeth will strike against one another, leading to material wear and loud noise. When a remotely operated shiftable multiple-disk clutch is used instead of the manually shiftable tooth clutch, there is a danger that the loading of the ship's propeller shaft by the ship's driving engine will suddenly be interrupted in the event of a failure of the clutch closing pressure, so that the ship's driving engine overspeeds and is damaged. Another problem in all drive systems is that there is only limited space available for its installation in the ship or other engine compartment.